It is the story of Wales' cities and counties summed up in a neat graphic tool.
Our widget allows you to compare the growth of the nation's county areas over the last 200 years.
So compare Cardiff's extraordinary growth (dented only momentarily with a dip in the 70s) with the troubles of the once-thriving ironmasters' mecca that was Merthyr.
The fishing village that became a capital
See how Swansea and Newport were once significantly larger than the fishing village that has since grown to become Wales' capital.
But while all the cities have seen steady growth, it has been a different story entirely in the Valleys.
Areas like Blaenau Gwent and Rhondda Cynon Taf saw their population boom in the 19th Century.
But that came to an abrupt stop when the coal trade peaked in the early 20th Century - and their population figures have been dwindling ever since.
And experts expect the trend to continue with
Have a go yourself...
Enjoyed using this?
